- As if earthquake-ravaged Indonesia doesn't have enough
to worry about, now scientists warn that a Sumatran super-volcano might
blow its top at any time.
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- If it does, the blast will toss hundreds of thousands
of cubic kilometres of rock and ash into the atmosphere, dwarfing the eruptions
of Krakatoa, Mount St Helens, Pinatubo and any conventional volcanic explosion
of the past tens of thousands of years.
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- "These super-volcanoes are potentially the greatest
hazard on Earth, the only greater threat being an asteroid impact from
space," said Ray Cas, a vulcanologist with Monash University in Melbourne.
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- Professor Cas said a "major tectonic event"
could be enough to trigger a deadly super-volcanic eruption.
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- The likelihood that the Toba ñ the largest super-volcano
on Earth ñ will erupt has increased significantly due to geological
stresses generated by the recent quakes.
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- Worse, Toba sits directly atop the faultline running
down the spine of Sumatra. That is where seismologists say a third quake
might strike.
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- Because of the increased risk, Professor Cas called for
increased monitoring of Toba.
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- "With enough precursor information and signals like
gas releases, we (could) warn of a significant eruption in days, weeks
or months," he said.
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- Professor Cas's call follows a report early this month
to the British Government's Natural Hazard Working Group by the Geological
Society of London. The report called for increased awareness of the risks
posed by super-volcanoes and development of mitigation strategies.
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- Vulcanologist Stephen Self of Britain's Open University
said a super-volcanic eruption might cover an entire continent with ash
that could take decades to erode.
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- "(Such an eruption) could result in the devastation
of world agriculture, severe disruption of food supplies and mass starvation,"
he told the online journal LiveScience.
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- Professor Cas said super-volcanoes tended to erupt in
2000-year cycles. The Toba super-volcano last erupted 73,000 years ago.
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